Fluid pressure control mechanism



2 Sheets-Sheet 1 Oct. 12, 1948. w. A. EATON FLUID PRESSURE CONTROL MEcHANIsM Filed May 51, 1945 W. A. EATON FLUID PRESSURE CONTROL MCHANISM Oct. 12, 1948.

2 Sheets-Sheet 2 Filed May" 31, 1945 .m .WSN 1 Ektwwp Patented Oct. 12, 1948 FLUID PRESSURE CONTROL MECHANISM Viilfred A. Eaton, Elyria, Ohio, assignor to Bendix-Westinghouse Automotive Air Brake Company, Elyria, Ohio, a corporationrof Delaware Application May 31, 1945, Serial No. 596,963

(Cl. 'i4-335) 8 Claims.

This invention relates Ito iiuid pressure contro-l mechanism, and more particularly to mechanism of the type adapted to remotely control the selection and establishment vof various gear ratios in the transmission of the motor vehicle.

It has previously ,been proposed to provide mechanisms of this type for remotely controlling the selection and establishment of the gear ratios in the transmission of the motor vehicle, this being accomplished by providing selectively operable control valves at the operators station and uid pressure operated cylinders adjacent the transmission for actually selecting and establishing the desired gear ratio. In one particular form of mechanism, a gear shifting memiber has been provided which is movable laterally to select any one of the gear shift rails in the transmission, and movable longitudinally to move the selected rail to establish a desired gear ratio, these lateral and longitudinal movements being eiected by means of a pair of fluid pressure operated cylinders having their axes arranged substantially at right angles to each other. These cylinders have been controlled by various valves in the operator control valve mechanism, and in View of the fact that the ycylinders operate along diierent axes, it has been customary to provide interlocking mechanisms of various types in order to insure positive selection and establishment of the gear ratio selected by the operator. Mechanisms yof the above type are readily adapted to control the establishment of ysix different gear shift ratios, but it has been found that the interlocking mechanisms previously proposed were not effective to positively insure the establishment of I'the selected gear ratio in connection with a mechanism of this type, and it is accordingly an lobject of the present invention to provide positive interlocking mechanism in a system of the above type for insuring the positive selection and establishment of desired gear ratios by the operator in a transmission -of the six speed type.

It has zalso been possible in systems of the above type wherein two right angul'arly arranged `cylinders have been utilized to control the establishment of siX different gear ratios, for the operator lto inadvertently establish the wrong gear ratio, and it is an object of the present invention to provide means for lovercoming this diiculty.

A further object of the invention is lto provide, in a mechanism of the above type, means for insuring the positive selection and establishment of any one of five or six gear ratios with a simpliand fare not designed for the purpose of theV limits of the invention, reference being had to this purpose to the appended claims.

In the drawings, wherein similar reference characters refer to similar parts through the several views: Fig. 1 is a perspective diagrammatic view, partially in section, of a gear shift control mechanism constructed in accordance with the principle of the present invention, and

Fig. 2 isa View, partially in section, of the operators control valve shown in Fig. 1.

Reiering more particularly to Fig. l of the drawing, it is pointed out that the mechanisml shown is adapted to |be `applied to a transmission of the type having three gear shift rails arranged in parallel, the position of these gear shift rails, not shown, being indicated by the position `of fthe arrows R!, 2 3 and li--5. A `casing 4 is provided for the gear shift mechanism, and is provided at its right hand portion with a cylinder 5 having a pist-on B slidably mounted therein fand provided with a leftwardly extending pis-ton rod l. A gear shifting member or lever B is rotatably mounted on the left end of the piston rod 'l and is restrained against longitudinal movement on the rod by means of collars 9 and i9 rigidly attached by suitable means to the rod. The lower end of the member 8 is shown 'as coinciding with the line 2 3, and it will Ibe apparent `that the lower end of the member may ,be moved along t'his line in response to the movement voi the piston in its cylinder. lIn View of the fact that the member is rotatably mounted on the piston rod l, it will also :be understood that the member may be rotated on :the piston rod in such a manner lthat a plane extending through the center line -oi the mem- .ber and through the axis of the piston rod will coincide either with the line R-I or with the line 1?.-5, and assuming that shift rails of conventional type are placed in the positions sho-wn by t'he above lines, it will be understood that the member 8 may be rotated in such a manner that the lower end will engage any one of such shift rails. The portion lof the member 8 above the piston rod 1 is provided with lan elongated tooth portion II Aadapted to engage a notch I2 formed on a second piston rod I3 mounted in a plane at right angles to the axis of the piston rod 1 and provided with -a piston I4 slidably mounted in a cylinder I5. Thus on movement lof the pis- -ton I4 and rod I3, the memsber 8 may be rocked 4about the piston rod 'I in either direction in order to position the member .to engage lany.

desired shift rail in the transmission of the vehicle. As heretofore stated, the gear shift rails are not shown, since this particular type of power gear shift is generally Well known to those skilled in the art, but it will be understood that the lower end of the shift member 8 is adapted to selectively engage notches formed in the low and reverse shift rail, the second and third speed vshift rail, or the fourth and fifth speed shift rail, subsequent m-ovement of the member to the left -or right in response to movement of the piston rod 1 serving to engage any one of the above gear ratios.

The right end of the cylinder 5 is closed by means of a cover plate I6, andthe left end is closed by means of a cover plate I1 having a bore I8 adapted to slidably receive the piston rod 1, a seal I9a serving to prevent leakage from the cylinder at this point. The piston 6 is normally maintained in the neutral position shown by means of springs I 9 and 2i) positioned in the right and left ends of the cylinder respectively. In order that the piston may be definitely maintained in neutral position with a predetermined force, the springs are of the so-called preloaded type, the spring I9 being interposed between the cover plate I6 and a flange 2I formed 0n the left end of a spring cage 22 slidably mounted in the cylinder 5 and bearing at its left end against the right faceV of the piston. Shoulder 23 is formed in the cylinder 4 as shown, and further movement of the spring cage 22 to the left is prevented by means of a flange 24 formed on the right end thereof and adapted to engage the shoulder 23. Thus the spring I9 may be inserted in the cylinder between the flange 2l and the cover plate I in a precompressed condition without, however, forcing the piston 6 to the left beyond the position shown. In like manner, the portion of the cylinder to the left of the piston 6 is provided with a shoulder 25, and a spring cage 26, likewise slidably mounted in the cylinder, is provided with a flange 21 bearing against the left side of the piston, and a flange 28 adapted to engage the shoulder 25, the spring being interposed in a precompressed condition lbetween the cylinder cover plate I1 and the ange 21 of the cage. Thus the piston is normally maintained against movement in either direction from the position shown by a force which is determined by the degree of compression of the springs I9 and 20. The piston I4 in the cylinder I5 is likewise maintained in neutral position in the same manner by means of springs 29 and 30 and spring cages 3| and 32, these springs being preloaded between the cages and cylinder and covers 33 and 34 respectively in the same manner as shown in connection with cylinder 5. The end cover 33 Vis provided'with a bore 35 in which the piston rod I3 is slidably mounted, a seal 36 serving to prevent leakage at this point. The piston rod I3 is also extended to the left from the piston/I4 through a bore 31 formed in the end cover 34 and provided with a Y suitable seal 38. Y

It will appear from the foregoing that when right end of the conduit 5I: In like manner, the i valve 40, shown at the left, is provided with Van fluid pressure is admitted to the right end of the cylinder 5, the piston 6 and the member 8 will be forced to the left against the tension of the `spring 20, while on application of uid pressure to the left end of the cylinder, the piston and member will be forced to the right from the neutral position shown against the tension exerted by the spring I9, these springs serving to return the piston to the position shown whenever fluid pressure is exhausted from both ends of the cylinder. In like manner the admission of uid pressure to the left end of the cylinder I5 will move the piston I4 and the piston rod -I3 to the right in order to rotate the member 8 in a clockwise direction,`while on admission of fluid pressure to the right end of the cylinder, the piston and rod will be moved to the left to rotate the member 8 in a counterclockwise direction from the position shown. Thus selection of the desired gear shift rail is controlled by the is controlled by the operation ofthe pistonV 6.`

Control of the supply of fluid pressure to the ,y

above described Vcylinders is accomplished by means of an operators controlvalve generally designated in Fig. 1 by the numeral 39, this control valve mechanism being-provided with six separate control valve assemblies which arenot shown in detail, but which may be generally designated on the left side of the control valve mechanism by the numerals 4I), 4I and 42, Vand on the right side of the control valve mechanism by the numerals 43, 44 and 45, it being understood that each set of three Yvalves is arranged in parallel, and that each of the valves'is adapted to be individually selected or operated by means of an operator controlled lever 46, as will be more fully described hereinafter. The top of the valve mechanism 39 is provided with a guide plate 41 which serves to guide the movement of the control lever, this plate being provided with transverse slots 48, 49, and 50; and with a longitudinal slot 5I which serves to interconnect the central portions of the above named slots, thus permitting the control lever to move from the longitudinal slot to one of six different valve op-v erating positions. The valves 4I), 4I and 42 are` provided with outlet conduits 52, 53 and 54,while the valves 43, 44 and 45 are provided with outlet conduits 35, 56 and 51, these loutlet Y conduits being connected with the gear shift mechanism ,at the vehicle transmission, as will be described more fully hereinafter. The valves 40, 4I and 42 are provided with a common exhaust outlet 58, the Valves 43, 44 and 45'being provided with a common exhaust outlet 59.` Fluid pressure is supplied to the control valve mechanism by means of a conduit 68, connected to a suitable source of fluid pressure, not shown, and a conduit'BI connected to the conduit 60 serves to supply uid pressure at all times to the inlet chambers'of all of the above named control valves.'

Referring more particularly to Fig. 2 of the drawings, an end view. of the control valve mechanism 39, taken partially in section, shows the` construction of the individual valves, such as the valves 43 and 43, and referring to the right hand 'portion of the drawing, it will be noted that the Y valve 43 is provided with an inlet chamber 62 which is in communication with a passage 63 which is common to thelinlet chambers of the valves 43, 44 and 45, and is connected with -the are; 1,160

inlet chamber 64 connected with an inlet passage 55, vthis passage in turn being common to the inlet chambers ofthe valves 49, 4lil and 42, and being connected tothe left end of conduit y(i l. The control valve 43 is vprovided with an outlet chamber 66, this chamber being separated from the Vinlet chamber by meansof a ported partition E1. Communication is normally prevented between the inlet chamber 6'2 and the outlet chamber 66 by means of an inlet valve 68 normally maintained in the position shown by means of a valve spring 69 interposed between the left surface `of the partition and an exhaust valve 1U connected with the inlet valve Ylill by means of a valve stem ll. A cylindrical bore 12 Vis formed at the left end of the outlet chamber 66, and a valve operating plunger 13 is slidably .mounted in the bore. Movement of the plunger to fthe left beyond the position 'shown is prevented by means of a shoulder 1'4 'formed adjacentt'he right hand ofthe plunger, and the plunger is normally maintained in the position shown by means of a spring 15 interposed between the left hand side of the partition and the 'shoulder '14. An exhaust chamber 16 is formed in the wall-of the bore 12, and this chamber, as well as similar chambers formed in connection with valve mechanisms 44 and 45, are in communi'c'a'tion at all times with the exhaust connection 59. A bore 11 is formed in the plunger 13 as shown, and the right end of the bore is adapted, on movement of the plunger to the right, to en- Vgage the left end of the exhaust 'valve "19, further movement of the plunger in the above direction serving to open the inlet valve in order to permit the now 'of uid pressure from the chamber S2 through the ported partition 61 into fthe outlet chamber 65. With the valve operating plunger in the position shown, the right hand of the bore 11 is in communication with Vthe out-let chamber, and this bore in turn is connected with the exhaust `chamber 16 by means of ports 18 formed in the wall of the bore, the outlet chamber 635 as vwell as the corresponding outlet chambers of the valves 44 and 1&5 thus normally being in communication with atmosphere, v`this communication in the case of the valve 33, being Vthrough the bore 11, the `ports 18, the outlet chamber n'l5 and the outlet connection 59. YThe opera-tors control lever 46 is slidably mounted for rotation on a shaft 1-'9 supported by the casing of the valve mechanism, it thus being possible to not only rotate the lever on the shaft T9, but to also move the lever longitu'dinally along the shaft in order to permit the lever to register with any one of the guide slots 4'8, 49 or 50. A-cam Alill is 'formed ait the lower end 'of the lever, a portion 8| of 'the cam being normally in engagement with the spherical end Lor the lplunger 1-3. On rotation of "the lever and foam in a counterclockwise direction, 'the effective radius or the cam increases, and the plunger 13 is moved to Athe right to first close the exhaust valve, vand thereafter open the inlet valve 6s in order to admit fluid pressure ffrom the inlet charnber 52 to the outlet chamber 56, this outlet chan'rber being connected to the outlet vconduit 55, 'shown vin Fig. 1, by means of 'a passage 82 formed in the casing.

vThe left hand valve 49, shown in Fig. 2, i's 'provfided with similar p'arts including a valve operatffing plunger 83, and in View of the arrangement of the cam, it will be understood that during rot-ation of the cam and lever in a lcounterclocllzwise direction no movement 'is imparted to the valve operating plunger 873, due to the contour of the earn. The valve 40 is provided with an outlet passage 84- and an exhaust chamber '85 connected with the exhaust conduit 58 which is common to similar chambers in the valves 4l and 4'2, `and `it will be understood that on clockwise rotation of the cam and lever from the position shown, the plunger 83 will be moved to the left by the cam, operating inlet and exhaust valves 86 and 81, provided in the valve 40, to disestablish comm-unication between the Aoutlet passage 84 andthe exhaust chamber 85 and to establish communication between the outlet passage and the vflu-id pressure supply passage l65 which is connected 'to the supply conduits 6| and 60 'as heretofore desoribedt It is also desirable that means be provided to maintain the lever in one or the other ofthe above described valve operating positions, and to this end slight `depressions 88 and 89 `are formed on the surface of the cam as shown, the depression I88 being adapted to engage the valve operating plunger 13 when the camis rotated in 'a 'counterclockwise direction tooper'a'te this '-plunger. Since the valve operating plunger 13 is normally urged to the left by the spring 15, and is further urged to the left by the air 'pressure 'in the outlet 'chamber 66 when the latter 'is connected with "the inlet chamber 62, itwill be understood vthat the depresision 88 cooperates with the plunger to provide a detent action which serves to maintain the cam and lever in valve operating position. -In like manner, the depression 89 cooperates 'with the plunger 83 to maintain the cam and lever in valve operating position when the cam is rotated in a clockwise direction. The plunger I83 is likewise urged 'to the right by the spring 90 :in the valve 49, and in order to insure positioning of the cam and lever in neutral position when desired by the operator, cam portions 9| and 92 are adapted to engage the ends of plungers 13 `and 83 respectively in order to exert a detent action on the cam, it being understood that during -longitudinal movement of the cam and lever from one set of valve operating plungers to another, the lever is prevented from movement out of neutral position by the longitudinal slot 5l in the cover plate 41.

As heretofore stated, it is necessary to provide interlocking means -for controlling the flowof fluid pressure from the `opera'tors control valve to the shift cylinder 5 in order to insure that the shift member 8 'is positioned at all times in accordance with the positioning of the operators control lever 46, and to this end, a casing 93 'is suitably Vattached to the left en'd of the cross shift fcylinder l5 and is provided with a pair of cylindrical 'chambers 94 'and 95 formed longitudinally of 4the casing and concentric with the piston rod `|3 which is extended to vthe left through the chambers as shown. The two chambers are separated by means of a partition 96, -a bore 91 in the lpartition beingv in sliding engagement with the piston rod, and being provided 'with a -seal 98 to prevent leakage between the chambers. The left I'end of the chamber 95 is closed as shown, and a bore 99 is slidably engaged by the left end 'of the piston rod, leakage at this point being prevented Vby means of a seal m0. The chamber -94 is connected with the left end of the cylinder f5 by means 'of a conduit IBI, while the chamber 95 is connected 'with the right end of the above cylinder by means of a conduit |02, it thus being apparent that iluid pressure supplied to and exhausted from the right end of the cylinder 5 must iiow through the chamber .94, while `fluid pressure for the left end of the cylinder `rii'ust now through the chamber 95.

The upper portion of the 'casing 93 is provided 7 with a series of three valves for controlling the iiow of uid pressure through the chamber 94 and an additional series of three valves for controlling the flow of uid pressure through the chamber 95. The piston rod I3 is provided with a cam |03 in the chamber 94 for operating the first set of valves, as well as with a cam |04 in the chamber 95 for operating the second named set of valves. These valves are arranged preferably in parallel relationship, and referring first to the valves for controlling the flow of fluid pressure through the chamber 94, it will be noted that a series of parallel bores |05, |05 and |01 are adapted to slidably receive corresponding valve operating plungers |08, |09 and I|0. The upper ends of the bores |05, |06 and |01 are provided with enlarged portions I, I2 and I3, the upper ends of these bores being adapted to be closed respectively by ball valves ||4, I|5 and |6, these valves being urged downward respectively by means of valve springs I |1, I I8 and I |9 interposed between'the upper surfaces of the valves and a cover plate mounted on the casing. The upper ends of the valve operating plungers are extended for engagement with the corresponding valves, and the plungers are so dimensioned that with the parts in the position shown, and with the lower ends of the plungers |08 and ||0 in engagement with the surface of the piston rod I3 as shown, a slight clearance exists between the upper ends of the plungers and the lower sulfaces of the corresponding valves. The cam |93 is-so positioned on the piston rod I3 as to normally engage the center plunger |09 when the piston I4 is in neutral position, and the plunger |09 is thus normally raised sufficiently to maintain the center valve ||5 in open position. The bores ||2 and H3 are interconnected b5 passages |2| and |22, these latter passages being connected with the chamber 94 by passages |23 and |24. Chambers |25, |26 and |21, formed above the Valves and closed at their upper ends by means of the cover plate |20 are connected respectively to conduits |28, |29 and |30. Similar valve operating plungers |3I, |32 and |33 are slidably mounted in the left hand portion of the casing above the chamber 95 as shown, and chambers |34, and |35 are adapted to be closed at their upper ends by spring pressed balls |31,V |38 and |39 respectively. The plunger |32 is normally in engagement withthe cam |04 in order to maintain the valve |38 in open position when the piston |4 is-in neutral position, the plungers |3| and |33 riding on the upper surface of the piston rod with the piston in this position and allowing the valvesV |31 and |39 to remain closed. The chambers |34, |35 and |36 are interconnected by means of passages |40 and |4|, these passages in turn being connected with the chamber 95 by passages |42 and |43. Chambers |44, and |40 formed above the respective valves and closed at their upper ends by means of .cover plate |20, are connected respectively to conduits |41, |48 and |49, the flow of iiui-d pressure through these conduits, as well as the previously referred to conduits |25, |29 and |30, being controlled by the operators control valve mechanism 39, as will be more fully described hereinafter In order to provide connections between the operators control valve mechanism and the cylinders of the gear shift mechanism to insure proper control of the latter by the operator, the outlet line 55 is connected to the right end of a double check valve |50, this check valve being 8 of conventional design and being provided with a casing I5I having a plunger |52 slidably mounted therein and connected at its other end with the conduit |30 leading to the valvechamber |21. The double check valve casing is connected at its center with a conduit |53 connectedat its left end to the right end of the cylinder l5, the check valve being adapted with the parts in the position shown to permit communication between conduits |30 and |53, and being adapted on movement of the plunger to the left in response to the application of fluid pressure to the right 'end of the check valve through the conduit 55, to prevent communication between conduits |30 and |53 and to permit communication between conduits and |53. In addition, the conduit |49 is connected to the conduit 55 adjacent the right end of the double check valve. In like manner, a second double check valve |54, identical with the check valve |50, is connected at its right end with conduit |41, at its left end with conduit 54, and at its center with a conduit 55 connected to the left end of the cylinder I5, the conduit 54 also being connected with the conduit |28 adjacent the left end of the doublecheck valve |54, and the conduit 51 being connected with the conduit |41 adjacent the right end of the latter check valve.

40, connected to the valve chamber |45, and conduit 53 is a continuation of conduit |29, connected to valve chamber |26.

In the event the operator desires to select and engage the reverse gear ratio, the control lever 46 is moved to the left in slot 48, whereuponthe valve 43 is operated to disestablish communication between conduits 55 and 59 and to establish communication between conduits 5| and 55 in order to supply fluid pressure to the right end of between conduits 55 and |53, and fluid pressure is supplied to the right end of the cylinder l5 to move the piston I4 to the left. When this occurs, the lever 8 is rocked in a counterclockwise direction, and the lower end of the lever coincides with the line R-L As the piston moves to the left, the cam |04 is likewise moved to the left, rst allowing the valve |38 to close to prevent the flow of fluid pressure through the conduit |48, and thereafter opening the valve |39 in order to permit fluid Apressure to now from the conduitV V|49 into the valve chamber 95, and thence into the right end of the cylinder 5 through the -conduit |02. Since the conduit |49 is connected to the conduit 55 leading to the outlet chamber of theV valve 43, it will be understood that fluid pressure will be supplied to the valve chamber |46 as soon as the valve 43 is operated, and as the lower end of the lever 8 moves into a position coinciding with the line R--L the cam |04 will open the valve |39 to permit fluid pressure to iiow from the conduit |49 to the right end of the cylinder `5 ,through valve chamber |40, chamber |35, passages |4| and |43, chamber 95, and conduit |02. When this occurs, the piston 5 will move the rod 1 and the lever 8 to the left along the line R-I to `establish Y the reverse gear ratio. When the lever 46 is returned to neutral position, fluid pressure is released through the valve 43 fromthe right endY of the cylinder 5 and the right endk of the cylinder Conduit 50 is a continuation of conduitA with the art. When the lever 3 returns to neutral position along the line Rf-l, the lower end will register with a notch in the second and third speed shift rail, not shown, and will therefore be returned to neutral position by the action of the spring 30 in the cylinder I5. Selection and engagement of first speed is effected by moving the control lever 4 6 to the right in slot 48, whereupon the valve 40 is operated to disestablish communication between conduit 52 and exhaust conduit 58, and to establish communication between conduit 6| and conduit 52. When this occurs, fluid pressure is supplied by the valve to the conduit |30, and since this conduit is connected to the left end of the double check valve |50, the plunger |52 is again moved to the position shown in the drawing, and communication is established between conduits |30 and |53. Thus fluid pressure is supplied to the right end of cylinder I5 through conduit 52, conduit |30, double check valve |50' and the conduit |53, and at the same time fluid pressure is supplied to the valve chamber |21 to conduits 52 and |30. With the piston I4 in neutral position, the valve |I6 is closed, and serves to prevent the flow of fluid pressure from the conduit |30 to the main shift cylinder. Since fluid pressure has been supplied to the righil end of the cylinder I5, however, the cam |03 is moved tothe left to permit closing of the valve I I5, and thereafter operates the plunger IIO to open the valve II6. When this occurs, fluid pressure is supplied `to the left end of the cylinder 5 from the conduit |30 to chamber |21, bore I I3, passage |22, passage |23, chamber 94, and conduit IOI. Since the piston |4 has again been moved to the Jleft in order .to rotate the lever 8 in a counter- .clockwise direction in such a manner that the lower end of the lever coincides with the line R-I, the supplying of fluid pressure to the left end of the cylinder 5 will move the piston 6, the piston rod 1 and the lever 8 to the right in order to establish the rst speedgear ratio. As explained in connection with the establishment of rst gear ratio, movement of the control lever 46 to neutral position in Aslot 4B will operate the valve 40 to. exhaust fluid pressure from cylinders 5 and i5 to permit the pistons and the lever 8 to return to the neutral position shown in the drawing.

Since the lower end of the lever 8 is normally maintained in alignment with the line 2 3 by the operationof vthe preloaded springs 29 and 30 in ,the cylinder I5, it will be apparent that no movement of the piston I 4 is necessary during the .establishment of second or third speed. In order to establish second speed, the control lever 46 is moved to the right in slot 5| and thereafter to the left in slot 49, 4thus operating the valve 44 to prevent communication between conduit 56 and exhaust c onduit 59, and to establish communication between conduit BI and conduit 56. When this occurs, uid pressure is supplied to the valve chamber |45 through conduit 56 and its extended portion |48, and since the valve |38 is normally maintained in open position by the cam |04 when .thepiston I4 is in neutral position, uid pressure is supplied directly to the right end of the cylinder .5 from the conduit |48 through Athe valve chamber |45, the passage |35, passage |40, passage I42, chamber 95, and conduit |02, thus moving the piston 6 and the shift lever 8 to the lef-t along the line 2 3 in order to en-gage second s peed. The selection and engagement of third speed is accomplished by moving the control 1e- `ver to the extreme right in the slot 49, whereupon the valve 4| is operated to prevent communication between conduits 53 and 58, and to establish communication between conduits 6| and 5,3, As heretofore stated, conduit |29 is a continuation of conduit 53 and fluid pressure is therefore supplied to the left end of the cylinder 5. through the above conduits, the valveV chamber |26, the bore |52, passage 52|, passage |24, chamber 94, and conduit 50|, it being noted that the valve II5 is normally main-tained in open position by the cani |93 i411 order to permit the passage of fluid pressure from the valve chamber |26 to the bore I I2@ As theipressure increases in the left end of the cylinder 5, the piston 6 andthe lever 8 are moved to the right along the line 2 3, and the'third speed ratio is established. Engagement of' fourth speed. is accomplished by returning the lever 46 to lieu- -ltl-'al position in the slot 49, moving it to the right Vin slot 5I, and thereafter tothe extreme left position the slot 5|).Y This serves to operate :the valve i5` to establish communication between .conduits ,5| ,and 51, thusV supplying fluid pressure't-o k,the val-ve chamber |44 through conduits 51 and |44, .and to the left end of the cylinder I5 through `the double check valve |54 and conduit |55. The normally closed valve I 31 preventsvthe how "of fluid pressure to the right end of the cylin'der' until the valve l|37 has been opened by the movement `of the cam |94 to the right. bsince fluid pressure is supplied to the left end of t-he cylinder ,l5 as stated above, the cam |04 is eventually moved to the right to permit closing of the valve |38 and to Aopen the valve |31, whereupon fluid pressure is supplied to the rightend of the .cylinlder from the conduit |41 through valve chamber |44, bore |34, passage |40, pass-age |42, chamber 95 and conduit 02. The movement of the piston |.4 to the vright rotates the lever 8 in a clockwise direction and into alignment with the line 4 5,

.and when this alignment Vis effected, the valve |31 is opened by ,the cam |04 to permit the oW .of ,fluid pressure to the right end of the cylinderf, .as Vabove described, whereupon the lever is moved to the vleft along the line 4 5 to engage fourth speed gear ratio. The ,engagement and selection of frith speed is effected by moving the control -lever tothe extreme right in slot 50. This operates .the .v alve 4 2 to establish communication between conduit :6I and conduit 54. Conduit 54 is connected with 'conduit |28, and fluid pressure is therefore supplied to the valve chamber |25, but is prevented from flowing to the left end of ,the c ylinder5 by the normally closed valve I I4. Since .the con-duit 54 is connected tothe left end of vthe check valve 154, the -lagtter is effective when fluid pressure is Lsupplied thereto to establish communication betweenconduits 54-and |55 leading'rto the :left .end ofthe cylinder |15, and the piston isconsequently moved to `the right to again move ythe lever into Y alignment with the `line 4 5, in the event this lever .has returned Y.to the neutral ,positionshown during movement of the controllever 45 from the extreme left to the extreme right in theslot50. As piston kI4 .moves to the right,`the plunger ,|08 is operated by thecam .|03 to open the valve IIA, and fluid pressure is supplied to the left end of the cylinder y5 through the valve chamber |25, the bore III,p;as sage ,I2 passage 11,24, chamber94 and conduit IDI', and the piston v6 j:and shift lever y 8 are moved to the right ,to establishthe fiftlrspeed gear ratio.

In the operations of motor vehicles equipped ,with mechanism of this type, it is often found desirable,to` shift frornr'st to third speed, from third to Viifth speed, or from second vto fourth speed, and in some of the-previous control mechaafirieo' nisms provided, it has been found difficult to accomplish these shifts with assurance that the movement of the shift lever 8 would correspond to the movement of the operators control lever 46. In shifting from first to third speed, for example, it will be noted that in both cases the control lever and the piston 6 move to the right from neutral position in order to effect the establishment of the selected gear ratio, and unless proper interlocking means are provided, rapid movement of the control lever 46 from first to third speed position may result in the shift lever 8 returning to rst speed position rather than moving to third speed position as desired, this being due to the fact that without the provision of the necessary interlock valves operated by the piston I4, the left end of the cylinder is not sufciently exhausted to permit the lever 8 to fully return to neutral position before the pressure in the left end of the cylinder is again increased by the operation of the valve v4| on movement of the control lever 46 to third speed position. With the present construction, however, it will be noted that with the control lever in neutral position, conduits |48 and |29 are the only ones which can supply fluid pressure to the cylinder 5, these conduits being adapted respectively to supply fluid pressure to opposite ends of the cylinder through the passages heretofore described. Although the control valves 40, 42, 43 and 45 are all adapted to supply fluid pressure to the cylinder 5 on corresponding movement of the control lever I I, it will be noted that with the parts in the position shown, none of these valves can supply fluid pressure to either end of the cylinder 5 due to the fact that conduits |30, |28, |49, and |41 are blocked respectively by the normally closed valves H6, II4, |39, and |37. As heretofore stated, when the lever 8 is in reverse position, for example, it is prevented from rotating toward the line 2 3 by the second and third speed shift rail except when the piston 6 is in neutral position, and this likewise applies when the lever 8 is in a position to establish first, fourth or fifth speeds thus insuring that the corresponding interlock valves for these speeds will be held open until the piston 6 returns to neutral position and insuring the eX- haust of fluid pressure from the cylinder I5 through one or the other of the interlock valves. Consequently, the piston I4 is inoperative to rotate the lever 8 and to move the cams |04 and |03 to operate the above referred to valves except when the lower end of the shift lever 8 is in alignment with the line N-N, and the control lever 46 may be moved to any desired gear position with the assurance that the piston 6 will return fully to neutral position under the action of springs 20 and I9 beforeffluid pressure is again admitted to either end of the cylinder 5 to again move the piston 6 away from neutral position to establish a gear ratio. Due to the arrangement of the double check valves |50 and I 54 with respect to the connections leading from the operators control valve mechanism to the gear shift mechanism, this desirable result is accomplished in a simple and eflicient manner with a minimum amount of equipment.

While the invention has been illustrated and described herein with considerable particularity, it is to be understood that the invention is not limited to the form shown, but may take other forms, as will be readilyk understood by those skilled in the art. Reference will, therefore, be had' to the appended claims for a definition of the limits'of the invention.

1. A power-operated control mechanismV fora transmission gearing of theY type having a coinbined selector and shifter member having V'a neutral position and movable from 'one selected plane to another selected plane and movable in either direction in either of said planes to establish a selected gear ratio comprising power means for moving said member from one plane to the other, a separate power means for effecting shifting movement of the member from neutral position in either direction in each of said planes to a gear ratio establishing position, and means for controlling the supply of power to both said power means including separate pairs of power control devices for controlling the supply of power to said power means to effect movement of said member to each of said gear ratio establishing positions, and means controlled by the operation of the rst named power means for controlling the operation of one device of each pair. y

2. A power-operated control mechanism for a transmission gearing of the-type having a combined selector and shifter member having a neutral position and movable from one selected plane to another selected plane and movable in either direction in either of said planes to establish a selected gear ratio comprising power means for moving said member from one plane to the other, a separate power means for effecting shifting movement of the member from neutral position in either direction in each of said planes to a gear ratio establishing position, and means for controlling the supply of power to both said power means including a pair of individually operable power control devices each operable separatelyto supply power to the firstnamed power means to move said member into one of said planes, a second pair of individually operable power control devices each operable separately to supply power to the first named power means to move said member into the other of said planes, and separate power control means serially connected between each of `said devices and the secondv named power means and controlled by the operation of the first named power means for controlling the direction of movement of said member by said second named power-means in each 'of said planes.

3. A power-operated control mechanism for aL yoperable power control devices for supplying power to the power means for moving said member to each of said gear ratio establishing positions, separate power control means serially connected between each of said devices and the second named power means and controlled by the operation of the first named power control means for controlling the supply of power to the second named power means, means for supplying power from either of one pair of said devices to said rst named power means to move said member into said one plane, and means for supplying power from either of another pair of said 13 devices to said rst named power means to move said member into said another plane.

4. A power-operated control mechanism for a transmission gearing of the type having a combined selector and shifter member having a neutral position and movable from one selected plane to another selected plane and movable in either direction in either of said planes to establish a selected gear ratio, said mechanism including a double acting uid motor having a piston operatively connected to said member and adapted to move the latter to one or the other of said planes, a second double acting iiuid motor having a piston operatively connected to said member and adapted to move the member in either direction from neutral position in either of said planes to gear ratio establishing positions, and means for controlling the operation of said member including a plurality of control valves each selectively and individually operable to control the ow of fluid pressure to said cylinders to effect movement of said member to one of said gear ratio establishing positions, means including a double check valve for connecting either of one pair of said valves with one end of the iirst named cylinder, means including a second double check valve for connecting either of another pair of said valves with the other end of the first named cylinder, a third pair of control valves each respectively connected in series between one end of the second named cylinder and one valve each of said rst and second named pair of valves, a fourth pair of control valves each respectively connected in series between the other end of the second named cylinder and each of the other valves of said rst and second named pair, and means controlled by movement of the iirst named piston for simultaneously opening or closing one or the other of the third named pair of valves and one or the other of the fourth named pair of valves.

5. A power-operated control mechanism for a transmission gearing of the type having a :combined selector and shifter member having a neutral position and movable from one selected plane to another selected plane and movable in either direction in either of said planes to establish a selected gear ratio, said mechanism including a double acting uid motor having a piston operatively connected to said member and adapted to move the latter to one or the other of said planes, a second double acting fluid motor having a piston operatively connected to said member and adapted to move the member in either direction from neutral position in either of said planes to gear ratio establish-ing positions, means for returning the member to neutral position, and means for selectively supplying iiuid pressure to said Icylinders to effect movement of said member to any one of said gear ratio establishing positions including four selectively 4and individually operable control valves each operable to supply uid pressure to said cylinders to eifect movement of the member .to one of said gear ratio establishing positions, means for connecting either of one pair of said valves with one end of the first named cylinder, means for connecting either of the remaining pair of said valves with the other end of the first named cylinder, a third pair of valves each respectively connected in series between one end of the second named cylinder and one each of said rst and second named pair of valves, a fourth pair of valves each respectively connected in series between the other end of the second named cylinder and the other valves of said first and second named pair, 'a cam operable for selectively opening one or the other of the third named pair of valves, a second cam for selectively opening one or the other of said fourth named pair off valves, and an operative connection between said cams and the rst named piston.

6. A power-operated control mechanism for a transmission gearing of the type having a combined selector and shifter member movable in either direction from one plane into second and third planes and movable in either direction in each of said planes to a gear ratio establishing position to establish any one of six gear ratios, means for normally positioning said member in said one plane and in a neutral position in said one plane, a double acting iiuid actuator having a pressure responsive element connected with the member adapted on movement in one direction t-o move, the. member into the second named plane and on movement in the other direction to move the member into the third named plane, a second fluid actuator having a pressure responsive element connected with the member adapted on movement inone direction or the other to correspondingly move the member in said planes, and means for controlling the supply of fluid pressure to said actuators to selectively elfect es.- tablishment of any one ofv said six gear ratios including a group of three separate selectively operable valves for supplying iiuid pressure to one end of the second named actuator, a second group of three selectively operable valves for supplying fluid pressure to the other end of the second named actuator, means for connecting one valve in each group with one end of the :first named actuator and another valve in each group with the other end of the rst named actuator, a, third group of three control valves each connected in series between said one end of the second named actuator and each valve of the first named group, a fourth group of three control valves each connected in series between the other end of the second named actuator and each of said second named group of valves, means for selectively operating the valves of said third and fourth named groups for simultaneously moving a selected valve in each of said groups to open position, and an operative connection between said valve operating means and the pressure responsive element of the first named actuator.

'7. A power-operated control mechanism for a transmission gearing of the type having a combined selector and shifter member having a neutral position and movable from neutral position into two different planes and movable in either direction when in at least one of said planes to a plurality of gear ratio engaging positions, said mechanism including means for positioning said member in neutral position, a double acting fluid actuator having a pressure responsive member connected with the member for moving the latter into one plane or the other, a second double acting fluid actuator having a Dressure responsive element connected with themember to move the latter in said planes, and means for controlling the flow o-f fluid pressure to said actuators including separate selectively operable selector valves for controlling the movement of said member to each of said plurality of positions, separate control valves connected in series between the selector valves and the second named actuator, means for connecting certain of said selector valves with one end of the first named actuator, means for connecting certain other of .15 said Selector valves With the other end of said first named actuator, and means controlled by the movement of the pressure responsive element in the rst actuator for opening some of the separate control valves when i'luid pressure is supplied to said one end of the first named actuator and for opening the other control valves and permitting closing of said some control valves when the other selector valves are operated to supply uid pressure to the other end of said rst named actuator.

8. A power-operated control mechanism for a transmission gearing of the type having a combined selector and shifter member movable in one plane or another to establish a plurality of different gear ratio engaging positions, said mechanism including a fluid actuator having a pressure responsive element connected with the member for positioning the latter in one plane or the other plane, a fluid actuator having a pressure responsive element connected to the'member for moving thelatter in said planes to said gear ratio establishing positions, separate selector valves having valve operating elements each operable to control the ow of iiuid pressure to said actuators to eiect the establishment of one of said gear ratio establishing positions', interlocking valves controlled by the movement of the pressure responsive element in the rst named actuator for directing the flow of fluid pressure from the selector valves to the second named actuator to insure movement of said member to the gear'rati'o 's`- tablishing position corresponding to the selector valve which is operated to supply, fluid pressure to the actuators, and means for selectively and individually operating said selector valves includ- Y ing an operator-controlled lever mounted for 'movements in diierent planes, a cam connected with said lever operable on movement of the leverV in one plane to select a desired selector valve and on movement .thereof in another plane to depress the operating element of the selected valve, mean for biasing said valve operating elements in -ca engaging direction, and portions formed on sai elements for yieldingly maintaining said cam and lever in valve operating and neutral positions.

WILFRED A. EATON.

REFERENCES CITED I The following references are of record in the vfile of this patent:

UNTTED STATES PATENTS Number Name Date 2,137,959 Turek Nov. 22, 1938 2,157,592 Casler May 9, 1939` 2,189,679 Sanford Feb, 6, 1940 2,200,013 Sanford May '7, 1940 2,226,660 Eaton et al Dec.r31, 1940, 2,358,846 Andres Sept. 26, 1944-. 

